Police cars block the driveway at Gorham Middle School Friday just after 3 p.m. An officer on duty said investigators are responding to a bomb scare at the location, and no students remained in the building at that time.

On Thursday, Gorham police were advised of a bomb threat in the area of the middle school, Gorham police Sgt. Michael Nault said in a news release issued early Friday evening. He said students were sheltered in place during the initial investigation and eventually dismissed at the regular time.

Shortly after 1 p.m. on Friday, police were informed of a more specific threat in the vicinity of the middle school.

Students again were kept inside the school and dismissed at the regular time. Because of the threat, students who normally walk home from school instead were bused to Gorham High School and dismissed from there.

In addition, all after-school activities were canceled, Nault said.

While police investigated Friday’s incident, they prevented vehicles from approaching the middle school. Two marked Gorham Police Department cruisers were stationed at the end of the Weeks Road driveway leading to the school turning away cars.

Gorham Middle School is the latest Maine school to have been disrupted by a bomb threat in recent weeks. Richmond middle and high schools, which share a building in the Sagadahoc County town, were emptied for approximately 90 minutes early this month while police searched for a bomb after the word was written on a bathroom stall.

Oak Hill middle and high schools in Wales have had particular trouble with bomb threats recently. Both were evacuated this week after officials in those schools discovered the word “bomb” written in girls bathrooms in each building — in the middle school on Monday and the high school on Tuesday.

A 14-year-old girl was charged with filing a false police report in the Oak Hill Middle School case on Wednesday, but nobody was charged in the high school case.

Oak Hill High School was evacuated on April 2 due to a bomb threat as well.

Police have not found bombs in any of the schools recently searched after threats.

Anyone with information about the Gorham bomb scares is asked to call Gorham police at 839-5581.